The hip joint is a ball-and-socket joint: the head of the femur (thigh bone) is the ball, and
the pelvic bone forms the socket. Hip dysplasia occurs when the ball is loose in the socket.
"Hip dysplasia can lead to pain, degenerative changes, and severe arthritis," says Dr.
Charles W. Smith, an orthopedic veterinary surgeon at the University of Illinois Veterinary
Medicine Teaching Hospital in Urbana. Depending on such variables as your dogﾒs age,
size, and degree of pain, hip dysplasia can be managed well with conservative treatment or
surgery.

"The cause of hip dysplasia is multi-factorial," says Dr. Smith. "Fast-growing large and giant
breed dogs are most likely to develop hip dysplasia." Genetics accounts for about 25
percent of your dogﾒs chance of developing hip dysplasia. Other factorsﾗsuch as
high-calorie diets (high-protein diet or puppy chow fed too long) and
over-supplementationﾗincrease your dogﾒs chance of developing this degenerative
disease.

"Early signs of hip dysplasia include an unwillingness to stay out in the cold, difficulty in
rising on the hindlegs or climbing stairs, and lack of stamina in work or play. As the disease
gets worse, some dogs will shift their weight forward off the rear quarters. Dogs with later
stages may bunny hopﾗhop on both hind limbs when walkingﾗor may have intermittent
lameness that becomes chronic after age four. You may feel the jointﾒs looseness, and in
chronic cases you may hear cracking noises," explains Dr. Smith. Signs may begin as early
as 5 months of age.

By the time your dog is two years old, radiographs will show if he should be eliminated
from a breeding program because of dysplasia. "Whether the dog is showing signs or not,
dogs who show looseness of the joint on radiograph or palpation should not be included in
a breeding program because of the genetic factor of the disease," stresses Dr. Smith.

To reach a definitive diagnosis your veterinarian will have to take radiographs (X rays).
"However, the severity of clinical signs do not always correlate well with the severity of the
radiographic signs," stresses Dr. Smith. "Treatment should be based on the amount of pain
and lameness the individual dog is showing, not on the radiographs."

In the young patient that has occasional bouts of pain and lameness, Dr. Smith suggests
conservative therapy. Conservative treatment may include weight reduction, exercise
restriction, and a pain and inflammatory regulator.

"Any surgical correction of hip dysplasia is a serious procedure young or mature. Some
dogs who show radiographic changes never develop significant lameness, so I prefer not to
subject them to a surgery they may never need."

Surgeries for the younger patient include triple pelvic osteotomies (TPO) and
intertrochanteric varus osteotomies. TPOs are suggested for immature patients who have
not developed irreversible cartilage or bone changes in the hip joint. This surgery could
achieve pain-free activity, stabilization of the hip with natural tissues, and reduction of
progression of radiographic signs of degenerative joint disease.

In the mature patient, Dr. Smith re-emphasizes that it is important to treat the individual
dogﾒs signs and not the radiograph. "All dogs first diagnosed with hip dysplasia should be
treated conservatively," says Dr. Smith. Conservative therapy is the same for younger and
older dogs.

While your pet is undergoing conservative therapy, closely monitor your petﾒs pain level.
"Response to conservative therapy really depends on the dogﾒs threshold of pain and the
ownerﾒs ability to monitor the dog," says Dr. Smith. "Dogs that respond to therapy initially
and then deteriorate are surgical candidates."

Surgical treatments, such as femoral head and neck ostectomies and total hip replacements
for older dogs, are salvage procedures that eliminate the diseased joint and attempt to
replace it with a non-painful substitute.

Femoral head and neck ostectomies are most effective for dogs that weigh less than 60
pounds. In this procedure, your veterinarian removes the ball part of the hip joint. "The leg
will return to function between 6 weeks and 6 months. The leg will appear shorter and the
degree of function will vary. Some animals return almost to full function, while others show
abnormalities of the gait. Range of motion will definitely be decreased, but so will the
amount of pain," explains Dr. Smith.

Total hip replacements are good for large mature dogs that are unresponsive to
conservative therapy and are otherwise healthy animals. This procedure replaces the
diseased joint with a high-density plastic socket and a stainless steel ball that is cemented
into place. "This procedure is more expensive than the femoral head and neck ostectomy,
but the results are very good. Dogs typically return to full function of the limb within 1
month. Pain is also reduced to a minimum," says Dr. Smith. Complications, including
dislocation of the joint post-operatively or loosening of the cement that holds the joint
together, occur in 5-10 percent of total hip replacements. If the prosthesis gets infected,
removal of the artificial joint and cement is required to cure the infection.

Before buying a large-breed puppy, ask the breeders whether their dogs are certified "hip
dysplasia free" by the Orthopedic Foundation for Animals. This will not guarantee a puppy
free of hip dysplasia, but it will reduce the likelihood.

If you notice a problem in your growing pup or mature dog, have it checked right away by
your local veterinarian.